When core network devices are interconnected, it is necessary to interconnect multiple chassis. Generally, chassis are required to work without interruption even in the case of being faulty or under maintenance, which imposes high requirements on the reliability and maintainability of the core network devices. In the prior art, two or more switch fabric units (SFUs) for interconnecting chassis are configured in each chassis to avoid service interruption in the case that the chassis is faulty or under maintenance.
Currently, interconnected chassis are distributed in a star structure. That is, in all chassis to be interconnected, one is a main chassis, and others are all connected to the main chassis. Through the main chassis, the whole network is connected, and data is exchanged between chassis. Generally, two SFUs for exchanging data between chassis are configured in each chassis. All boards in this chassis perform data exchanging with the boards in other chassis through the SFUs. One SFU of each chassis is connected to one SFU of the main chassis to form a communication plane; and another SFU of each chassis is connected to another SFU of the main chassis to form another communication plane. The two planes work in an active/standby mode to improve the reliability of the system.
In the existing connection mode, all chassis perform data exchanging through a main chassis. If the main chassis is faulty or under maintenance and the whole chassis needs to be powered off, all chassis are disconnected, and the data exchanging between the chassis fails, which seriously affects the service. Therefore, this connection mode is defective in terms of reliability and maintainability; meanwhile, the load on the main chassis is increased because all chassis are interconnected through the main chassis.